Dangerous U.S. Spiders
When people see me pick up a spider with my bare hands and throw it outside, their typical reaction is “You are crazy! How do you know that spider isn’t dangerous?”
Here is the answer, out of approximately 3,000 different species of spider in North America, only two species from the U.S. are considered deadly. These are the brown recluse spider and the black widow spider. These spiders are easy to identify (See the first two on the above chart. The brown recluse has a violin shape on top of the cephalothorax and the black widow has an hourglass shape on the underside of the abdomen) and therefore pretty easy to avoid being bitten by, but even if you are bitten, it is very unlikely that you would die if you sought medical attention. In the U.S. there are only an average of four spider deaths reported per year.
There are other spiders in the U.S. that are somewhat dangerous but not deadly. If you are bitten by one of them you may experience some unpleasant symptoms but not death. You can see some of these spiders in the chart above.
*Note: If a small child or pet is bitten by one of these venomous spiders they are much more likely to be seriously affected.
Please stay aware of spiders that could be dangerous and only handle spiders that you know are not significantly dangerous, but also recognize that spiders are very beneficial creatures and try not to kill them whenever possible, dangerous or not! It’s just rude. Just let them be, even spiders that do have potent venom are often not aggressive. They just want to be left alone.
Sources:
http://emedicine.medscape.com/article/772196-overview#a0199
http://rodneysouthern.hubpages.com/hub/How-to-Identify-Poisonous-Spiders
http://www.termite.com/spider-identification.html#blackwidow
https://sites.google.com/site/venomousdangerous/spiders/n-america-s-most-venomous-spiders
http://cru.cahe.wsu.edu/cepublications/eb1548/eb1548.html